Back to results
US 9,435,200 B2Granted
Determination of thermodynamic properties of a fluid based on density and sound speed
AssigneeSchlumberger Technology Corporation
InventorAnthony Robert Holmes Goodwin
Life of this patent
Estimating the term…
Abstract
Variable volume systems and methods of use thereof described herein are capable of making calibrated determinations of fluid properties and phase behavior of a fluid sample. The determinations can be calibrated based on one or more calibration functions, such as system volume corrected for pressure and temperature variations. Cross-checking the results of measurements can be used to determine accuracy of the calibration or monitor for leaks or other anomalies of the variable volume systems. The variable volume systems can be implemented in a well logging tool and are capable of being calibrated downhole.
Claims19
A system, comprising:
- a fluid sample container that alters a temperature or a pressure of a fluid sample;
- an optical fluid analyzer (OFA) that determines a compressibility of the fluid sample at each of a plurality of pressures or temperatures, wherein the compressibility comprises an isothermal compressibility κT or an isentropic compressibility κS, wherein the isothermal compressibility is defined by the equation
- κ
- T
- =
- -
- 1
- V
-
- (
- ∂
- V
- ∂
- p
- )
- T
- and the isentropic compressibility is defined by the equation
- κ
- S
- =
- -
- 1
- V
-
- (
- ∂
- V
- ∂
- p
- )
- S
- where V is volume, p is pressure, S is entropy, and T is temperature;
- a sound speed component that measures a speed of sound in the fluid sample at each of the plurality of pressures or temperatures;
- and
- an analysis component that calculates, at each of the plurality of pressures or temperatures, a density of the fluid sample based at least in part on the compressibility and the speed of sound, wherein the analysis component determines one or more thermodynamic properties of the fluid sample based at least in part on the density and the speed of sound, wherein the one or more thermodynamic properties comprises at least one of a property indicative of heat capacity of the fluid sample, a property indicative of an expansivity of the fluid sample, or a property indicative of an adiabatic index of the fluid sample.
32 more elements
A method, comprising:
- capturing a sample of a fluid;
- determining, for each of a plurality of pressures in a range of pressures, a density, a speed of sound, and a heat capacity of the sample, comprising:
- measuring the speed of sound in the sample for each of a plurality of temperatures in a range of temperatures;
- determining a density for the sample for each of the plurality of temperatures, wherein determining the density comprises measuring a compressibility of the sample, the compressibility comprises an isothermal compressibility κT or an isentropic compressibility κS, wherein the isothermal compressibility is defined by the equation
- κ
- T
- =
- -
- 1
- V
-
- (
- ∂
- V
- ∂
- p
- )
- T
- and the isentropic compressibility is defined by the equation
- κ
- S
- =
- -
- 1
- V
-
- (
- ∂
- V
- ∂
- p
- )
- S
- where V is volume, p is pressure, S is entropy, and T is temperature;
- and
- estimating the heat capacity of the sample for each of the plurality of temperatures;
- and
- determining one or more thermodynamic properties based at least in part on the determined density, the speed of sound, and the heat capacity, wherein the one or more thermodynamic properties comprise at least one of a heat capacity of the sample, an expansivity of the sample, or an adiabatic index of the sample.
35 more elements
A system, comprising:
- means for pressurizing and depressurizing a fluid;
- means for measuring a compressibility of the fluid, wherein the compressibility comprises an isothermal compressibility κT or an isentropic compressibility κS, wherein the isothermal compressibility is defined by the equation
- κ
- T
- =
- -
- 1
- V
-
- (
- ∂
- V
- ∂
- p
- )
- T
- and the isentropic compressibility is defined by the equation
- κ
- S
- =
- -
- 1
- V
-
- (
- ∂
- V
- ∂
- p
- )
- S
- where V is volume, p is pressure, S is entropy, and T is temperature;
- means for measuring a speed of sound of the fluid;
- and
- means for determining, based at least in part on the speed of sound and a density of the fluid calculated based on the compressibility and the speed of sound, one or more of a heat capacity of the fluid, an expansivity of the fluid, or an adiabatic index of the fluid.
32 more elements
Dependencies are inferred from the claim text.